> From Tim's description, it sounds like the _video_ ram is the problem, > and that is what I was talking about (hence the referral to SGC ram - > where the chips have similar leg layout) > They are recovered chips supplied by Peter, and they tend to make bad > contact in the sockets. > Certainly stripes on screen will be video ram.
This is exactly the problem I have with my Q40 (as Tony well knows as he has reseated the Video RAMs for me on a number of occasions!) The last fix lasted approx. 15 minutes and a subsequent fix I did myself had a similar result. It was not an inexpensive machine to buy and I haven't had enough use of it to be able to afford to write it off just yet. I was wondering if someone might be able to come up with a permanent solution, e.g. removing the sockets and soldering the RAMs in place; or maybe there are some spare chips with longer pins (some of the pins on mine seem too short to be gripped properly by the sockets); or perhaps creating a little piggyback Video RAM board that could be plugged in somehow. I'm keen to get the Q40 back into full time service again. Are those chips still available new? Ian. ----- Original Message ----- From: "Tony Firshman" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, February 19, 2004 10:01 PM Subject: Re: [ql-users] Q40 Problem > > On Thu, 19 Feb 2004 at 11:16:57, > =?iso-8859-7?B?IlBob2VidXMgUi4gRG9rb3MgKNbv3+Lv8iDRLiDN9Pzq7/IpIg==?= > wrote: > (ref: <[EMAIL PROTECTED]>) > > > > > >99.99% of the problem is caused by bad contacts on the SIMM sockets. > >Follow Tony's advise on cleaning them as he's the one that built yours > >so he knows which ones he used and how to clean them best. > > > >The SIMM sockets are not gold plated in the old Q40s (I am not sure > >that they are in the new ones either... haven't seen the Q40i boards > >yet) > We are talking at cross purposes here. > > From Tim's description, it sounds like the _video_ ram is the problem, > and that is what I was talking about (hence the referral to SGC ram - > where the chips have similar leg layout) > They are recovered chips supplied by Peter, and they tend to make bad > contact in the sockets. > Certainly stripes on screen will be video ram. > > That area is also used for data storage, so is pretty critical. > ... and it is a lot more that .01% in the problem stakes! > > Simms can be a probelm too, but that would usually stop bootup. > -- > QBBS (QL fido BBS 2:252/67) +44(0)1442-828255 > tony@<surname>.co.uk http://www.firshman.co.uk > Voice: +44(0)1442-828254 Fax: +44(0)1442-828255 > TF Services, 29 Longfield Road, TRING, Herts, HP23 4DG > >
